Error: File System With Given Label Not Found

[Marek Paśnikowski]

Dear All

I am refactoring a freshly-installed system configuration
in the ORG Literate Programming style.  After each change
I do guix system reconfigure to catch mistakes and errors.

While following https://guix.gnu.org/manual/en/html_node/File-Systems.html
I encountered a new system error, when I tried to use the file-system-label 
procedure:

#+begin_src scheme
  (type "vfat")
  (mount-point "/boot/efi")
  ;; (device (uuid "4E57-A066"
  ;;                  'fat32))
  (device (file-system-label "izumi-esp"))
#+end_src

$ LC_ALL=C sudo guix system reconfigure config.scm -v 4
Password: 
/home/marek/src/izumi/config.scm:22:28: error: file system with label 
'izumi-esp' not found

$ ls /dev/disk/by-partlabel/
izumi-esp  izumi-swap  izumi-system

According to the manual, I should be able to do away
with the UUID identifier in my configuration.

Is this a regression or outdated manual?  Is there anything
I could do to be able to identify the partitions with labels?

===============================================================

Below is the full configuration file for those interested.

$ cat izumi.org
#+title: Configuration of the Izumi computer -*- mode: org -*-
#+author: Marek Paśnikowski
#+startup: content
#+property: header-args:scheme :noweb yes
#+property: header-args:scheme+ :noweb-prefix no

* Guix

https://guix.gnu.org/en/manual/en/html_node/index.html

** System Configuration

https://guix.gnu.org/manual/en/html_node/System-Configuration.html

*** Using the Configuration System

https://guix.gnu.org/manual/en/html_node/Using-the-Configuration-System.html

#+name: OPERATING-SYSTEM-DERIVATION
#+begin_src scheme :tangle config.scm
  (use-modules (gnu))

  (use-package-modules certs)

  (use-service-modules cups
                       desktop
                       networking
                       ssh
                       xorg)

  (operating-system <<OS-RECORD>>)
#+end_src

*** operating-system Reference

https://guix.gnu.org/manual/en/html_node/operating_002dsystem-Reference.html

#+name: OS-RECORD
#+begin_src scheme
  (kernel-arguments (append %default-kernel-arguments
                            (list "nomodeset")))
  (bootloader (bootloader-configuration <<BOOTLOADER-CONFIGURATION-RECORD>>))
  (keyboard-layout <<MAIN-KEYBOARD-LAYOUT-RECORD>>)
  (host-name "izumi")
  (mapped-devices (list (mapped-device <<ENCRYPTED-STORAGE-RECORD>>)))
  (file-systems (append %base-file-systems
                        (list (file-system <<EFI-PARTITION-RECORD>>)
                              (file-system <<SYSTEM-PARTITION-RECORD>>))))
  (swap-devices (list (swap-space <<SWAP-PARTITION-RECORD>>)))
  (users (append %base-user-accounts
                 (list (user-account <<USER-MAREK-RECORD>>))))
  (packages (append %base-packages
                    (list nss-certs)))
  (timezone "Europe/Warsaw")
  (locale <<LOCALE-STRING>>)
  (services (append %base-services
                    (list (service <<NETWORK-MANAGER-SERVICE-OBJECT>>)
                          (service <<NTP-SERVICE-OBJECT>>)
                          (service <<OPENSSH-SERVICE-OBJECT>>)
                          (service <<WPA-SUPPLICANT-SERVICE-OBJECT>>))))
#+end_src

*** file-systems

https://guix.gnu.org/manual/en/html_node/File-Systems.html

#+name: EFI-PARTITION-RECORD
#+begin_src scheme
  (type "vfat")
  (mount-point "/boot/efi")
  ;; (device (uuid "4E57-A066"
  ;;                  'fat32))
  (device (file-system-label "izumi-esp"))
#+end_src

#+name: SYSTEM-PARTITION-RECORD
#+begin_src scheme
  (type "xfs")
  (mount-point "/")
  (device "/dev/mapper/izumi")
  (dependencies mapped-devices)
#+end_src

*** mapped-devices

#+name: ENCRYPTED-STORAGE-RECORD
#+begin_src scheme
  (source (uuid "b06171fb-beb4-46b1-bac6-aa65675d240a"))
  (target "izumi")
  (type luks-device-mapping)
#+end_src

*** swap-devices

#+name: SWAP-PARTITION-RECORD
#+begin_src scheme
  (target (uuid "5fe1a209-6ff9-4586-a61c-19187d33ba3b"))
#+end_src

*** users

The list of user accounts ('root' is implicit).

#+name: USER-MAREK-RECORD
#+begin_src scheme
  (name "marek")
  (comment "Marek Paśnikowski")
  (group "users")
  (home-directory "/home/marek")
  (supplementary-groups (list "audio"
                              "netdev"
                              "video"
                              "wheel"))
#+end_src

*** keyboard-layout

#+name: MAIN-KEYBOARD-LAYOUT-RECORD
#+begin_src scheme
  (keyboard-layout "pl")
#+end_src

*** locale

#+name: LOCALE-STRING
#+begin_src scheme
  "pl_PL.utf8"
#+end_src

*** services

Below is the list of system services.  To search for available
services, run 'guix system search KEYWORD' in a terminal.

#+name: NETWORK-MANAGER-SERVICE-OBJECT
#+begin_src scheme
  network-manager-service-type
#+end_src

#+name: NTP-SERVICE-OBJECT
#+begin_src scheme
  ntp-service-type
#+end_src

To configure OpenSSH, pass an 'openssh-configuration'
record as a second argument to 'service' below.

#+name: OPENSSH-SERVICE-OBJECT
#+begin_src scheme
  openssh-service-type
#+end_src

#+name: WPA-SUPPLICANT-SERVICE-OBJECT
#+begin_src scheme
  wpa-supplicant-service-type
#+end_src
*** bootloader

#+name: BOOTLOADER-CONFIGURATION-RECORD
#+begin_src scheme
  (bootloader grub-efi-bootloader)
  (targets (list "/boot/efi"))
  (keyboard-layout <<MAIN-KEYBOARD-LAYOUT-RECORD>>)
#+end_src